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Vitamin D is a fundamentally critical nutrient that the human body requires to function properly. It plays an important role in musculoskeletal health due to its involvement in the regulation of calcium and phosphorus. Having a low level of vitamin D in the body may be detrimental for a wide range of health outcomes, including risk of osteoporotic and stress fractures, risk of CVD and some cancers, and lowering of the capability of the immune system. Vitamin D is an unusual nutrient; it is not a vitamin, in the true sense of the word but a pro-hormone. The main source of vitamin D is UV exposure, not dietary intake. Interestingly, there are two forms of vitamin D, vitamin D2 and vitamin D3, both of which are metabolised into 25-hydroxyvitamin D (25(OH)D) in the liver, the biomarker of vitamin D status. Vitamin D deficiency is a global public health problem, especially amongst older people and ethnic minority groups. The newest publication from the UK Government's Public Health England Department recommends that vitamin D intake should be 10 μg daily and this recommendation compares well (albeit lower) with other guidelines such as the Institute of Medicine recommendation of 15 μg for those aged 1–70 years and 20 μg for those 70 years or over. Few countries, however, have a specific vitamin D policy to prevent deficiency in populations. Finland leads the way, demonstrating impressive results in reducing population-level vitamin D deficiency through mandatory food fortification programmes. Collaboration between academia, government and industry, including countries from varying latitudes, is essential to identify long-term solutions to the global issue of vitamin D deficiency. This paper provides a narrative review of the evidence related to the role of vitamin D deficiency in health outcomes, outlines controversies regarding setting levels of adequacy, identifies the prevalence of vitamin D deficiency across the globe, and identifies population-level strategies adopted by countries to prevent vitamin D deficiency.
Second-harmonic generation of the relativistic self-focused chirped laser pulse in plasma has been studied with the exponential plasma density ramp profile in the presence of a planar magnetostatic wiggler. It is evident that the exponential plasma density ramp is helpful in enhancing second-harmonic generation as, with the introduction of the exponential plasma density ramp, self-focusing becomes stronger and hence, it leads to enhance the harmonic generation of the second order in the plasma. Also, it is observed that the efficiency of second-harmonic generation enhances significantly with an increase in the value of the chirp parameter. Further, the magnetostatic wiggler helps in enhancing the harmonic generation of the second order. This is due to the fact that dynamics of the oscillating electrons is altered due to the Lorentz force which, in turn, modifies the plasma wave and, hence, results in the efficient second-harmonic generation.
To assess the effect of tranexamic acid in head and neck surgical procedures.
A prospective, double-blind and randomised, parallel group, placebo-controlled clinical trial was conducted. Ninety-two patients undergoing various head and neck surgical procedures were randomised. Subjects received seven infusions of coded drugs (tranexamic acid or normal saline) starting at the time of skin closure. Haematological, biochemical, blood loss and other parameters were observed by the staff, who were blinded to patients’ group allocation (case or control).
Patients were analysed on the basis of type of surgery. Fifty patients who had undergone surgical procedures, including total thyroidectomy, total parotidectomy, and various neck dissections with or without primary tumour excision, were included in the first group. The second group comprised 41 patients who had undergone hemithyroidectomy, lobectomy or superficial parotidectomy. There was no statistical difference in blood parameters between both groups. There was a reduction in post-operative drain volume, but this was not significant.
Although this prospective, randomised, placebo-controlled clinical trial found a reduction in post-operative drain volume in tranexamic acid groups, the difference was not statistically significant between the various head and neck surgical procedure groups.
Universal depression screening in youth typically focuses on strategies for identifying current distress and impairment. However, these protocols also play a critical role in primary prevention initiatives that depend on correctly estimating future depression risk. Thus, the present study aimed to identify the best screening approach for predicting depression onset in youth.
Two multi-wave longitudinal studies (N = 591, AgeM = 11.74; N = 348, AgeM = 12.56) were used as the ‘test’ and ‘validation’ datasets among youth who did not present with a history of clinical depression. Youth and caregivers completed inventories for depressive symptoms, adversity exposure (including maternal depression), social/academic impairment, cognitive vulnerabilities (rumination, dysfunctional attitudes, and negative cognitive style), and emotional predispositions (negative and positive affect) at baseline. Subsequently, multi-informant diagnostic interviews were completed every 6 months for 2 years.
Self-reported rumination, social/academic impairment, and negative affect best predicted first depression onsets in youth across both samples. Self- and parent-reported depressive symptoms did not consistently predict depression onset after controlling for other predictors. Youth with high scores on the three inventories were approximately twice as likely to experience a future first depressive episode compared to the sample average. Results suggested that one's likelihood of developing depression could be estimated based on subthreshold and threshold risk scores.
Most pediatric depression screening protocols assess current manifestations of depressive symptoms. Screening for prospective first onsets of depressive episodes can be better accomplished via an algorithm incorporating rumination, negative affect, and impairment.
Background: Biallelic variants in POLR1C are associated with POLR3-related leukodystrophy (POLR3-HLD), or 4H leukodystrophy (Hypomyelination, Hypodontia, Hypogonadotropic Hypogonadism), and Treacher Collins syndrome (TCS). The clinical spectrum of POLR3-HLD caused by variants in this gene has not been described. Methods: A cross-sectional observational study involving 25 centers worldwide was conducted between 2016 and 2018. The clinical, radiologic and molecular features of 23 unreported and previously reported cases of POLR3-HLD caused by POLR1C variants were reviewed. Results: Most participants presented between birth and age 6 years with motor difficulties. Neurological deterioration was seen during childhood, suggesting a more severe phenotype than previously described. The dental, ocular and endocrine features often seen in POLR3-HLD were not invariably present. Five patients (22%) had a combination of hypomyelinating leukodystrophy and abnormal craniofacial development, including one individual with clear TCS features. Several cases did not exhibit all the typical radiologic characteristics of POLR3-HLD. A total of 29 different pathogenic variants in POLR1C were identified, including 13 new disease-causing variants. Conclusions: Based on the largest cohort of patients to date, these results suggest novel characteristics of POLR1C-related disorder, with a spectrum of clinical involvement characterized by hypomyelinating leukodystrophy with or without abnormal craniofacial development reminiscent of TCS.
Three different high entropy-alloys consisting of six elements (Ti, Zr, V, Cr, Ni, and Fe) with varying Fe content were synthesized by using the RF induction melting technique. All the as-cast, slow-cooled, and rapidly quenched alloys exhibit C14 Laves phase, and it is found to be stable at high temperature. A lattice contraction has been observed with the addition of Fe. To the best of our knowledge, this is the first report on the synthesis of a single-phase high-entropy complex intermetallic compound in the hexanary alloy system. It has been shown that the thermodynamic calculations following Miedema’s approach and the parametric approach utilizing several descriptors comprising configurational entropy, mixing enthalpy, atomic size mismatch, electronegativity, and valence electron concentration favor the stability of the high-entropy multicomponent Laves phase.
Enhanced harmonic generation of second order based on exponential density ramp in plasma has been noticed. It is well known that self-focusing of pump laser induces a transverse intensity gradient, which gives rise to the plasma wave at the pump frequency. Highly intense Gaussian laser with exponential density ramp profile generates a second harmonic pulse in plasma. It is noticed that the amplitude of second-harmonic pulse varies periodically with the distance and reaches its peak value in the focal region. Further, it is found that exponential plasma density ramp is useful for stronger self-focusing, which lead to rise second harmonic generation (SHG). Wiggler magnetic field provides the additional angular momentum required for second harmonic photon and aids in growing of resonant process. One may clearly see that exponential plasma density ramp imparts a major role in enhancing the SHG in plasma. Further, the combined effect of exponential density ramp and wiggler magnetic field boosts the SHG in plasma.
Evaluation of eleven candidate probiotic Lactobacillus strains isolated from human milk showed that some of the strains were well endowed with desirable cell surface and attachment attributes. The cell surface properties (hydrophobicity, auto-aggregation, attachment to collagen and HT-29 monolayer) of probiotic Lactobacillus species of human milk origin were compared with reference probiotic/ non-probiotic species and pathogenic strains. The bacterial adhesion to hydrocarbons (BATH) was determined using three aliphatic (Chloroform, n-Hexane and n-Octane) and two aromatic (Toluene and Xylene) solvents. Maximum affinity of Lactobacillus strains towards chloroform and toluene indicated the presence of low electron acceptor/ acidic surface components on cell surface of most of the strains. The highest value of per cent hydrophobicity was recorded with chloroform in HM1 (L. casei) (97·10 ± 3·35%) and LGG (98·92 ± 1·24%). A moderate auto-aggregation attribute was observed in all of our Lactobacillus isolates. Only HM10, HM12 and HM13 exhibited comparatively enhanced precipitation rate after 7 h of incubation period. The adhesion potential to collagen matrix was highest in LGG (26·94 ± 5·83%), followed by HM1 (11·07 ± 3·54%) and HM9 (10·85 ± 1·74%) whereas, on HT-29 cells, HM8 (14·99 ± 3·61%), HM3 (13·73 ± 1·14%) and HM1 (11·21 ± 3·18%) could adhere effectively. In this manner, we noticed that although the cell surface properties and adhesion prospective of probiotic bacteria were strain dependent, five of our isolates viz. HM1, HM3, HM8, HM9 and HM10 exhibited promising cell surface properties, which could be further targeted as indigenous probiotic.
The objective of this study was to compare the preoperative management and outcome of neonates with duct-dependent critical CHD with fetal versus postnatal diagnosis.
Patients referred with CHD to our centre from January 1, 2009 to December 31, 2010 were enrolled prospectively. Live births with a critical form of CHD, a gestational age ⩾36 weeks and a weight ⩾2 kg at birth, and the intention-to-treat were included in this sub-study. Excluded were neonates with lethal non-cardiac and/or genetic anomalies.
In total, 129, 63 fetal and 66 postnatal, cases met the study inclusion criteria. All had received appropriate antenatal care, including a routine fetal anatomy scan. Both cohorts were comparable in weight, gestational age, and APGAR scores at birth. Unlike the postnatal cases, there were no deaths (0/63 versus 5/66; p=0.06) and no cardiac arrests (0/63 versus 9/63; p=0.003) before surgery or catheter intervention in those cases with a prenatal diagnosis of critical CHD. Moreover, newborns with fetal diagnoses were admitted earlier (median 0 (range 0–3) versus 2 (0–25) days; p<0.001) and were less likely to require preoperative ventilation (19/63 versus 31/61, p=0.03) and vasoactive medication (4/63 versus 15/61, p=0.006) than the postnatal cases.
Prenatal diagnosis of critical CHD in this study was associated with significantly shorter time intervals from birth to neonatal admission and the absence of life-threatening or fatal preoperative cardiac events. Increased efforts should be made to improve rates of prenatal diagnosis.
Propagation of a strong incident shock through a bed of particles results in complex wave dynamics such as a reflected shock, a transmitted shock, and highly unsteady flow inside the particle bed. In this paper we present three-dimensional numerical simulations of shock propagation in air over a random bed of particles. We assume the flow is inviscid and governed by the Euler equations of gas dynamics. Simulations are carried out by varying the volume fraction of the particle bed at a fixed shock Mach number. We compute the unsteady inviscid streamwise and transverse drag coefficients as a function of time for each particle in the random bed for different volume fractions. We show that (i) there are significant variations in the peak drag for the particles in the bed, (ii) the mean peak drag as a function of streamwise distance through the bed decreases with a slope that increases as the volume fraction increases, and (iii) the deviation from the mean peak drag does not correlate with local volume fraction. We also present the local Mach number and pressure contours for the different volume fractions to explain the various observed complex physical mechanisms occurring during the shock–particle interactions. Since the shock interaction with the random bed of particles leads to transmitted and reflected waves, we compute the average flow properties to characterize the strength of the transmitted and reflected shock waves and quantify the energy dissipation inside the particle bed. Finally, to better understand the complex wave dynamics in a random bed, we consider a simpler approximation of a planar shock propagating in a duct with a sudden area change. We obtain Riemann solutions to this problem, which are used to compare with fully resolved numerical simulations.
Fetal hydrops is a serious complication of immune-mediated congenital complete atrioventricular block. We present the case of a fetus with severe hydrops and profound bradycardia and an unusual favourable outcome. This case enhances the importance of considering the contribution of ventricular ectopic beats to the cardiac output when counselling and predicting outcome of complete heart block.
Central nervous system infections (CNSI) are a leading cause of death and long-term disability in children. Using ICD-10 data from 2005 to 2015 from three central hospitals in Ho Chi Minh City (HCMC), Vietnam, we exploited generalized additive mixed models (GAMM) to examine the spatial-temporal distribution and spatial and climatic risk factors of paediatric CNSI, excluding tuberculous meningitis, in this setting. From 2005 to 2015, there were 9469 cases of paediatric CNSI; 33% were ⩽1 year old at admission and were mainly diagnosed with presumed bacterial CNSI (BI) (79%), the remainder were >1 year old and mainly diagnosed with presumed non-bacterial CNSI (non-BI) (59%). The urban districts of HCMC in proximity to the hospitals as well as some outer districts had the highest incidences of BI and non-BI; BI incidence was higher in the dry season. Monthly BI incidence exhibited a significant decreasing trend over the study. Both BI and non-BI were significantly associated with lags in monthly average temperature, rainfall, and river water level. Our findings add new insights into this important group of infections in Vietnam, and highlight where resources for the prevention and control of paediatric CNSI should be allocated.